Clamp



July 10, 1962 R, A, LAL| 3,042,987

CLAMP Original Filed April 2, 1956 INVENTOR. Romeo A @Z M ma@ A TTORNEYSUnited States Patent O CLAMP Romeo A. Lalli, Bridgeport, Conn. (1805Stratford Ave., Stratford, Conn.)

Original application Apr. 2, 1956, Ser. No. 575,470, now Patent No.2,889,865, dated June 9, 1959. Divided and this application Oct. 21,1958, Ser. No. 768,793

2 Claims. (Cl. 24-263) This invention relates to a manually operatedclamp means. More specifically, it pertains to a clamp adapted to gripthe edge of a sheet of metal or like material for exerting a pullingforce thereon.

The application is a division of my copending application Serial No.575,470, led April 2, 1956, now Patent No. 2,889,865.

It is an object of the'present invention to provide a clamp adapted toexert a stron-g gripping force and one which is readily movable into andout of clamping relation.

Another object of the invention is to provide a clamp which ispanticularly useful in the gripping of the end of a. metal sheet toprovide a pulling action thereon without damaging the sheet.

A further object of theinvent-ion is to provide a clamp whichisuniversally mounted to that it can accommodate itself to the directionof pull on the material gripped thereby.

A still further object of the invention is to provide a clamp having axed jaw member and a movable jaw member, with manually operated cammeans operably engaging the movable jaw member for shifting it relativethe iixed jaw member.

A feature of this invention resides in means whereby the opening andclosing of the jaw members of each unit is accelerated by simple rotaryKaction exerted on the actuating means of the clamping jaw.

Other -features and advantages will be apparent from the specificationand 'claims when considered in connection with the drawings in which:

1 1EIGURE 1 is a side view of an individual clamping Jaw.

FIG. 2 is an enlarged detail side View partly shown in section of theclamping jaw.

FIG. 3 is an enlarged detail front view partly shown in section of theclamping jaw.

The invention is directed to clamps of the type which are adapted togrip metal or sheets of like material and maintain a grip thereonagainst great amounts of pulling force. Though the clamp may be utilizedin a variety of ways and in conjunction with varied types of apparatus,reference hereafter is made, in order to facilitate the disclosure, toits use Iin an apparatus of the stretch press type.

According to the invention, -a base plate 29, of a stretch press or thelike can have mounted thereon one or more individually operated clampingjaw units 30. The individual units include an L-shaped base'portion 3-5having the base leg 35a slidably and pivotally mounted to the base plate29 for rendering the unit transversely adjustable along a slot 34. Astud l36 projecting upwardly through the slot secures the base portion35 of the unit to the base plate, the head 36a of the stud beingretained in the T-slot. The upwardly extending leg portion 35b of thebase portion 35 is provided with a transversely extending bore forreceiving a pin 37 about which a jaw member 38 is pivoted so that it maybe tilted with respect tothe base plate 29 as may be required, the upperportion of the jaw member being provided with a gripping portion 38a.Secured to the jaw member by suitable fasteners 39 is a bracket 40 whichis provided with a recessed por- 3,42,937 Patented `lilly 1G., 1962 rcpet 2 tion 4i, the recessed portion being adapted to be positionedopposite the gripping portion 38a of the jaw inember. Mounted in therecess 41 of the bracket is a second or normally retracted, movablymounted clamping jaw member 42. which is adapted yto be moved relativeto the iixed jaw member 38. This is accomplished by supporting themovable jaw member 42 on the bracket 40 by a plurality of pin members 43which are slidab'ly mounted in transversely extending bores 44, aportion of each bore 44 being enlarged to accommodate a coil spring 45which normally tends to urge the pin members 43 and attached jaw member42 into retracted position Iwithin the recess, as shown in FIG. 2. Ifdesired, the face of the movable Y jaw member 42 may be provided withserrations 42a to securely grip the material disposed between the jawmembers.

According to this invention, each clamping jaw unit 30 is provided withan individual operating means by which the jaws can .be individuallyoperated by a simple manual operation. As shown in the drawingg themeans for operating the movable jaws comprises a shaft 49 mounted in atransverse bore in the bracket 46 and having an eccentric cammingportion 4917 thereon which engages a dowel or roller 47 disposed in apassage 46, while roller 47 engages a recess 42b in the back of themovable jaw. Shaft 49 is rotatably mounted on the bracket 40 in atransversely extending bore, the ends 49a of the shaft being in bearingrelationship in the bore of the bracket. The eccentric camming portion4917 engages the roller 47 so that upon rotation of the shaft 49, theeccentricity of the intermediate portion 49h of the shaft displaces theroller 47 laterally, thereby advancing the jaw member 42 into clampingposition.

To facilitate rotation of the shaft 49, a manual operator 50 isprovided. As illustrated in FIGS. l tor 3, the operator comprises a rod`51 'having a knob 52 fixed to the upper end thereof, the rod 51 beingconnected to the shaft 49 intermediate the ends thereof. As illustratedin FIG. 2, the bracket 40 is provided rwith a slot 53 to accommodate forrotation of the handle for clamping and unclamping the jaw members.

AIn order that the movable jaw member 42 may be accelerated to itsclamping and unclamping position upon actuation of the actuating means50, the eccentric cam portion 4917 of the shaft is provided with alongitudinally extending recess 49C which is adapted to receive theroller 47. Therefore, `with reference to FIG. 2, it will be noted thatin normal, open ja-w position the roller 47 is in the-recess 42b of thejaw member and recess 49C of the cam. llhus, as the handle 50 isrotated, counterclockwise as viewed in FIG. 2, the shaft is rotatedcounterclockwise causing the cammin-g surfaces 49d of the eccentriccamrning portion 49b to engage the roller 47 to quickly cam or displacethe roller 47 laterally and to the right to move the clamping jaw 42into clamping position onto the marginal portion of a thin sheetmaterial (not shown) disposed between the jaw members. Because of theroller being normally seated in the recess 49e, it will be noted thatmaximum lateral displacement occurs during the initial rotation of thehandle whereby the roller 47 is forced out of the recess 49C to move themovable jaw member into clamping position. Continued rotation of theshaft 49 causes the outer camming surface 49d of the shaft to Wedge theroller against the movable jaw member to lock the same in clampedposition. Conversely, it will be noted that in unclamping the sheet, theshaft 49 is rotated clockwise from clamped position to the positionillustrated in FIG. 2. As a result, the gripping action is graduallyreleased until the instant the recess 49C is aligned with the roller 47,whereupon the latter is quickly snapped into seated position due to theaction of the springs Sniace? 45 normally biasing the jaw memberl 42 toopen position. Consequently, itY Will be Vnoted that theV acceleratedfeature of the novel4 clamping jaw herein described Vgreatly reduces.the amount of time involved in opening and closing of the clamping jawunits 30. Further, the clamping means of thisvinventioncomvprisesrelatively few parts which greatly reduces the cost ofVmanufacture and material, yet being sufficiently strong to resist theforces applied forstretching the material secured thereby. Furthermore,it will be noted that theV movable clamping jaw units are easily andreadilyfoperatedbetween the clamped or unclamped position by a simplerotary movement of the shaft.

Also, since relatively narrow jaw units are employed and are universallyadjustabley on the base plate, they Y may be positioned to assume anydesired predetermined setting to conform to that contour to be formed bythe forming die (not shown). Because of this important feature, themarginal edge portions of the sheet material can be reduced to a minimumand can correspond more accurately `to the Vcurvature to be formed bythe die proper, thereby substantially reducing the amount of Y materialrequired to be'trimmed from the finished article formed thereby.Further, the need of specialized clamps for each diierently shaped dieis eliminated; conse# quent-ly, a press having a universal type clamp asherein Vdescribed can be utilized in conjunction with' any of thevariously shaped dies required.`

Variations ,and modifications may be made the scope of Ithe claims andportions of the improvements may be used Without others.

I claim: 1. A clamping jaw unit comprising a jaw memberhaving a clampingsurface; a bracket removably `mounted on i said jaw member; a second jawmember movably mounted on said bracket, said movable Vjaw member beingadapted to be moved relative to said other jaw member and having a'clamping surface directed towardV the Vclamping surface of said otherjaw member; spring means normally urging said second jaw member awayfrom said first mentioned jaw member Ito maintain said jaw membersnormally spaced, and means for moving said second jaw member againsttheforce of said spring means and toward said first mentioned jawmember, said moving means including -a `dowel means mounted y011 saidbracket in engagement withthe movable jaw member at the rear of thecl-amping surface thereof, and ay shaftv rotatably mounted on saidbracket in iixed relation to said iirst jaw member yand having afportion forming eccentric cam means provided Awith a recess forreceiving said dowel means, said eccentric cam means being in cammingen'- `movable jaw member being adapted to be moved relative to saidother jaw member; Ispring means normally urging said second jaw memberaway from said rst-mentioned jaw' member to maintain said jaw membersnormally spaced; means for moving said second Ijaw member against theforce of said spring means and toward said inst-mentioned jaw member,said moving means including a dowel means mounted on said bracket inengagement with the movable jaw member; and a shaft rotatably mounted onsaid bracket in fixed relationlfto said first jaw member and Ihaving aportion formingeccentric cam means provided with arecess for receivingsaid dowel means, said cam means adjacent the recess being in cammingengagement with said dowel means forllaterally dis-v placing said dowelmeans for moving said movable jaw member relative to said other jawmember upon rotation of said shaft for clampingv and unclamping anarticle therebetween, said movable jaw member being formed with anelongate dowel-receiving recess adapted to receive and engage the sideof said dowel means for assuring complete engagement therebetween, saidrecess on the cam means being located in Yunclamping position to receivethe dowel means under the raction of the spring means to permit rapidopening of the jaws.

References Cited in the tile of this patent UNITED STATES PATENTS528,968 Peabody Nov. 13, 1894 586,359 Holt v July 13, 1897 983,419 AmesV Feb. 7, 1911 1,062,460 Y Hannan May 20, 1913 1,683,906 Mahoney 1-YSepL 11,1928 2,511,592.V i vKrafczyk L June 13, 19'50 2,607,070 WertZet A. Aug, 19, 1952 2,619,138, Marber V..' Nov. 25, 1952 2,753,915 Raymaj :anyY 10, 1956 Y FOREIGN PATENTS n l ,France ""',,...'.'-,r.'. Aug 5J

